/code-review ultra (ultrareview) always reports "no commits yet" regardless of actual git state

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Running /code-review ultra (also tried the deprecated /ultrareview alias) always returns:

Your current branch has no commits yet, so there is nothing to review. Commit your changes first, then rerun /code-review ultra.

...regardless of the actual git state. I tried three different states in the same repo, all pushed to a real GitHub remote (origin), and got the exact same error every time:

1. Uncommitted local changes on master, no new commits yet.
2. After committing directly to master (1 new commit ahead of what was previously on origin/master) and pushing.
3. After creating a separate feature branch from that commit, adding a second commit, and pushing the branch to origin (so the branch has 2 commits total, both present on GitHub, git status shows a clean working tree, git log shows the commits).

In all three cases /code-review ultra gave the identical error text. The built-in (non-ultra) /code-review worked fine and reviewed the actual diff correctly in the same session/repo state, so the repo/commits are definitely visible to other tooling.

Environment: Windows 11, Claude Code CLI, working directory is a local clone with origin pointing to a private GitHub repo (https://github.com/<owner>/<repo>.git), invoked via the Bash tool wrapping Git Bash (not PowerShell).

Expected: /code-review ultra should detect the commits on the current branch and launch the review, the same way the plain /code-review command does.

What Should Happen?

/code-review ultra should detect the commits on the current branch (which are present locally and on the pushed GitHub remote) and launch the multi-agent review, the same way /code-review correctly does today in the identical repo/branch state.

Error Messages/Logs

Steps to Reproduce

1. In a local git repo with an origin remote pointing to a real (private) GitHub repository, make some code changes and commit them (git commit).
2. Run /code-review ultra (or the deprecated /ultrareview alias).
3. Observe: "Your current branch has no commits yet, so there is nothing to review. Commit your changes first, then rerun /code-review ultra." - even though git log clearly shows the commit and git status shows a clean working tree.
4. Push the commit to origin (git push) and run /code-review ultra again - same error.
5. Create a new branch from that commit (git checkout -b feature-x), add a second commit, push the branch (git push -u origin feature-x), and run /code-review ultra again while checked out on feature-x - same error, even though the branch now has 2 commits, both visible on GitHub.
6. For comparison, run the plain /code-review (non-ultra) command in the same repo/branch state - it works correctly and reviews the actual diff.

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.220 (Claude Code)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

Terminal/Shell: Git Bash (the "Bash" tool in Claude Code on Windows wraps Git Bash / POSIX sh, not cmd.exe or PowerShell) - not in the dropdown list above, hence "Other".

I reproduced this from within a Claude Code session while working in the repo - happy to provide more detail (exact commands/output) if useful.